A. Field of the Invention
The embodiments of the present invention relate to a tenter frame rail, and more particularly, the embodiments of the present invention relate to a modular tenter frame rail.
B. Description of the Prior Art
In the process of finishing textile goods that are knit either completely or partially from synthetic materials, the goods are processed through a tenter frame where they are raised to a temperature sufficiently high to cause the material to be in a plastic state. The tenter hooks or pins on the frame fix the mechanical dimensions of the material and the process thus “sets” the material to that dimension.
Flexible sheet materials, such as lengths of fabric, are customarily dried or relaxed on these tenter frames. In a common form of these frames, the continuously advancing sheet is pressed by cylindrical brushes upon moving parallel rows of pins along each selvedge so that the sheet is held under lateral restraint as it is heated or subjected to other desired treatment as it is passed through the apparatus.
Conventional tenter frames are usually designed to dry and stretch a fabric web to its finished width, and include a pair of laterally spaced, elongate, and longitudinally movable first and second chains gripping the selvages or edges of the fabric web and advancing the web through a heating chamber. The chains slightly diverge during their advance through the heating chamber so as to apply lateral tension to the web as it advances therethrough.
Tenter frame chains with tentering clamp and needle combination links are used in horizontal hot air tentering frames. These chains also enable a further standardization of the guiding of the chains in single layer tenter frames. A typical tenter frame generally includes a plurality of tenter frame clips mounted on two endless chains guided by a pair of diverging tracks. The clips are adapted to shift from an open position to a closed position to grip the edges of a web of material, such as plastic film. As the web is moved in the machine direction being gripped by the clips that are moving on the diverging tracks, the web can be stretched transversely simultaneous with its longitudinal movement.
Tenter frame chains equipped with tentering clamp and needle combination links utilize so-called hammer-type tentering clamps for the clamping action, which have the drawback that their clamping action is limited and that an exact clamping width is not certain as is the case with the so-called roller probing tentering devices.
In the general operation of tenter frames, a web material enters the machine at one end where the web is engaged along its edges or selvages by a series of upwardly extending pins penetrating the web material. The pins are in turn secured to and supported by two endless tenter chains. The web material is thus held along its opposite edges by the upwardly extending pins for the full period of web travel through the tenter frame where it may be subjected to various and sundry treatments. For example, where the web material is a knitted or a woven fabric, it may simply be washed, shrunk, or stretched as desired and maintained in a desired dimensional state by the tenter chains as it dries. In any event, as web material moves through the tenter frame and reaches the exit end it becomes necessary to remove the web from the pins on the tenter chains for ultimate removal of the web from the tenter. At the same time in processing many web materials, it is necessary to trim the edges or selvages of the web material to remove the portion having been penetrated by the pins on the tenter chains. Otherwise a defect may be created in the web. Other webs, however, are unaffected by the pin holes and no trimming is necessary.
Numerous innovations for tenter frames and related devices have been provided in the prior art that will be described below, which are in chronological order to show advancement in the art, and which are incorporated herein by reference thereto. Even though these innovations may be suitable for the specific individual purposes to which they address, they each differ in structure, and/or operation, and/or purpose from the embodiments of the present invention in that they do not teach a modular tenter frame rail.
(1) U.S. Pat. No. 3,961,425 to Swanson et al.
U.S. Pat. No. 3,961,425 issued to Swanson et al. on Jun. 8, 1976 in class 34 and subclass 447 teaches an automatic temperature control system for a textile tenter frame having an oven section for heating the fabric in order to “set” its fibers in an essentially non-shrinkable state. The system operates to maximize the speed of the tenter frame while maintaining optimum heat set conditions. Fabric temperature from within the oven and initial moisture content data are furnished to a computer and processed with time-at-temperature target inputs to provide tenter frame speed control output signals.
(2) U.S. Pat. No. 4,017,722 to Swanson.
U.S. Pat. No. 4,017,722 issued to Swanson on Apr. 12, 1977 in class 700 and subclass 130 teaches a method and an apparatus for controlling the yield of fabric material from a tenter frame having spaced apart belts driven by drive apparatus and an overfeed roll at its entry end. In a start-up or style change mode of operation, a predicted dry yield is computed from data signals received before the fabric enters the tenter frame and is then compared with a target value to produce a control signal to the overspeed roll. In the steady state mode of operation, actual yield is computed from data taken at the output end of the tenter frame and is then is compared with a target yield value and thereafter modified by a correction factor proportional to variations in predicted dry yield computed from inputs taken at the entry to the tenter frame. The modified control signal again is applied to the overspeed roll.
(3) U.S. Pat. No. 4,065,838 to Jungpeter et al.
U.S. Pat. No. 4,065,838 issued to Jungpeter et al. on Jan. 3, 1978 in class 26 and subclass 94 teaches a device for opening tenter frame clips mounted on an endless chain carried by a sprocket wheel including a clip opening wheel rotatable on a common axis with the sprocket wheel. The clip opening wheel has an elastomeric peripheral rim. The clips have apparatus including a clamping surface and a pivotable clamping arm for clamping a web of material therebetween. The clamping arm is connected to a clip opening arm for pivoting the clamping arm into its open position. The clip opening arm is adapted to contact the elastomeric peripheral rim of the clip opening wheel as the clips are moved by the chain to open the clips. The elastomeric rim is of a material, such as polyurethane rubber having a hardness of 95 Shore A, reducing impact force as the opening arm is moved into contact with the rim during the opening of the clip. The rim may be fixedly mounted on the periphery of the wheel. Alternatively, the rim may move freely with respect to the wheel or the wheel may be freely rotatable about the common axis independently of the sprocket to help spread wear around the full circumference of the wheel.
(4) U.S. Pat. No. 4,232,434 to Pfister.
U.S. Pat. No. 4,232,434 issued to Pfister on Nov. 11, 1980 in class 26 and subclass 86 teaches an apparatus for supplying and attaching stiff crimpable sheet material at its selvedges to pin chains of a tenter frame, including overfeed apparatus for squeezing the material at each selvedge into a wavy shape and a pinning brush having a peripheral surface corresponding to the wavy shape of the selvedge of the material. The pinning brush synchronously moves with the selvedge of the material so that the crests and valleys of the peripheral surface of the brush are maintained in alignment with valleys and crests, respectively, of the selvedge.
(5) U.S. Pat. No. 4,403,379 to Grafen.
U.S. Pat. No. 4,403,379 issued to Grafen on Sep. 13, 1983 in class 26 and subclass 95 teaches a chain for a tentering frame, including links carrying so-called tentering hooks and needles for holding a fabric web to a movable conveyor forming the tentering frame. Each link carries an intermediate support member holding at its free end a journal pin below the margin of a fabric web. The journal pin supports an arched bail in a tiltable manner for movement between a working position and a rest position. The bail carries at its upper free end a further journal pin supporting a tentering hook in a tiltable manner. The first journal pin further supports a needle bar being tiltable with its needles into a fabric penetrating position or into an inoperative position. The needle bar preferably has a flat surface cooperating with the tentering hooks as a counter-holder when the needles are in a rest position.
(6) U.S. Pat. No. 4,497,096 to Richter.
U.S. Pat. No. 4,497,096 issued to Richter on Feb. 5, 1985 in class 26 and subclass 74 teaches a tenter frame drive wherein auxiliary power operated apparatus drives the sprockets at the entrance end of the chain runs, opposite the main drive at the exit end. The auxiliary drives remove the slack in the chains normally occurring at the exit end opposite the point of driving engagement of the sprockets in such a fashion as to avoid chattering of the chain and tenter clips while providing for a division of the forces so as to some extent reduce maximum tension in the chain and at the same time insure sufficient tension for proper gripping of the web at the entrance end of the tenter.
(7) U.S. Pat. No. 4,658,482 to Lechner.
U.S. Pat. No. 4,658,482 issued to Lechner on Apr. 21, 1987 in class 26 and subclass 93 teaches a tenter frame clip wherein the metal-to-metal contact between the clamping arm and the clip body is cushioned by elastomeric material. The cushioning material can be located on the clip body at the point of contact with the arm or on a rocker member hinged to the arm and located beneath a strike plate attached to the body.
(8) U.S. Pat. No. 4,788,756 to Leitner, Sr.
U.S. Pat. No. 4,788,756 issued to Leitner, Sr. on Dec. 6, 1988 in class 26 and subclass 51.4 teaches an apparatus and a method for correcting bow distortions in a fabric web during a tentering operation, including tension applying apparatus at each of the entry and exit ends of the tenter frame so that a tension is applied at each of the respective opposite ends of the tenter, with the applied tensions being directed in opposite directions. A sensor is for detecting either a leading or a trailing bow in the advancing web, and a control system acts in response to a signal from the sensor to change the tension applied at one or both ends of the tenter frame and thereby straighten the bow.
(9) U.S. Pat. No. 4,882,820 to MacKinnon et al.
U.S. Pat. No. 4,882,820 issued to MacKinnon et al. on Nov. 28, 1989 in class 26 and subclass 93 teaches a tenter frame chain including a plurality of links, each link including upper and lower interconnected loadbearing plates, and a low friction slide block sandwich between the upper and lower interconnected plates. The slide block is formed of material having a lower coefficient of friction than the interconnected loadbearing plates and includes a vertically disposed bearing surface located laterally outwardly beyond the lateral extent of one side of the upper and lower interconnected loadbearing plates. The vertically disposed bearing surface of the slide block contacts the bearing surface of the guide rail to reduce the frictional rubbing movement of the tenter chain against the vertically disposed bearing surface of each of the tenter chain guide rails as the tenter chain moves therealong.
(10) U.S. Pat. No. 4,926,529 to Hosmer et al.
U.S. Pat. No. 4,926,529 issued to Hosmer et al. on May 22, 1990 in class 26 and subclass 89 teaches a tenter frame wherein a chain is fabricated by press fitting a pin-receiving bushing constructed of Vespel and the like into a steel bushing and then boring a pin-receiving opening therein and utilizing wear strips constructed of Vespel in a dovetail configuration opposite the tenter chain providing a lubrication free tenter wherein the chain may be tensioned without excessive stretching.
(11) U.S. Pat. No. 4,939,825 to Kwack.
U.S. Pat. No. 4,939,825 issued to Kwack on Jul. 10, 1990 in class 26 and subclass 93 teaches a tenter frame clip being at least partially constituted from a lightweight polymeric composite material. The clips are employed in tenter frames as components of clip-chain assemblies for grippingly engaging and advancing thermoplastic film webs, fabrics, or foils through the tenter frame as the web is concurrently transversely stretched, and for the most part, are generally constituted from either cast iron or cast steel depending upon the type and size of the tenter frame and which may each readily weigh as much as five pounds and even higher. Each clip is able to exert a gripping force of up to 1500 to 2500 pounds.
(12) U.S. Pat. No. 4,972,560 to Baum.
U.S. Pat. No. 4,972,560 issued to Baum on Nov. 27, 1990 in class 26 and subclass 96 teaches an apparatus for a tenter frame feeding a fabric web to the nip region of vertical pins and cooperating rollers of a pair of endless belt assemblies transporting the web through a drying chamber. The apparatus includes a guide member guiding the web into the nip at a relatively steep angle, preferably in the range of 30° to 60°. The guide member can be supported on a pair of swivel supports, each of the swivel supports being movably supported on one of the endless belt assemblies. Additionally, the guide member can be a roller rotatable about its axial length, which can be rotated in synchronization with the feed of the web.
(13) U.S. Pat. No. 5,051,225 to Hommes et al.
U.S. Pat. No. 5,051,225 issued to Hommes et al. on Sep. 24, 1991 in class 264 and subclass 288.4 teaches an apparatus and a method for producing a drawn film by propelling individual carriages along opposed loops from a first speed abutted in stacks in carriage collection sections to a second speed space apart in a drawing section of a tenter frame and to a third speed in stack forming sections where the carriages return to the first speed in the stacks. First primaries positioned adjacent one part of each loop develop electromagnetic waves for engaging synchronous secondaries attached to active carriages to provide controlled spacing of the carriages and second primaries adjacent another part of the loop develop other electromagnetic waves for engaging hysteresis secondaries attached to active and to passive carriages to provide controlled abutting of the carriages.
(14) U.S. Pat. No. 5,067,214 to Hosmer et al.
U.S. Pat. No. 5,067,214 issued to Hosmer et al. on Nov. 26, 1991 in class 26 and subclass 89 teaches a tenter frame wherein a chain is fabricated by press fitting a pin-receiving bushing constructed of Vespel and the like into a steel bushing and then boring a pin-receiving opening therein and utilizing wear strips constructed of Vespel in a dovetail configuration opposite the tenter chain providing a lubrication free tenter wherein the chain may be tensioned without excessive stretching. Also, are lubrication-free tenter-clip jaw pivot bushings.
(15) U.S. Pat. No. 5,072,493 to Hommes et al.
U.S. Pat. No. 5,072,493 issued to Hommes et al. on Dec. 17, 1991 in class 26 and subclass 72 teaches an apparatus and a method for producing a drawn film by propelling individual carriages along opposed loops from a first speed abutted in stacks in carriage collection sections to a second speed space apart in a drawing section of a tenter frame and to a third speed in stack forming sections where the carriages return to the first speed in the stacks. First primaries positioned adjacent one part of each loop develop electromagnetic waves for engaging synchronous secondaries attached to active carriages to provide controlled spacing of the carriages and second primaries adjacent another part of the loop develop other electromagnetic waves for engaging hysteresis secondaries attached to active and to passive carriages to provide controlled abutting of the carriages.
(16) U.S. Pat. No. 5,081,751 to Pettigrew.
U.S. Pat. No. 5,081,751 issued to Pettigrew on Jan. 21, 1992 in class 26 and subclass 91 teaches an apparatus for limiting movement of tenter frame rails in order to avoid damage, particularly to chains, resulting from excessive movement, including a spring-biased plunger valve carried by the rail on one side of a rail junction, while the other side of the junction carries a member having a predetermined surface for actuating a switch when the member moves to an extreme position where it can no longer support the plunger against the resilient force of the spring causing a switch to be activated to deactivate the motor imparting transverse movement to the rails.
(17) U.S. Pat. No. 5,373,613 to Young, Jr. et al.
U.S. Pat. No. 5,373,613 issued to Young, Jr. et al. on Dec. 20, 1994 in class 26 and subclass 96 teaches a tenter frame for treating web materials, such as woven or knitted fabrics, film, or the like, to apparatus for removing a web from a tenter while controlling the web, and to a process for removal of a web from a tenter. A pair of endless-opposed tenter chains having a plurality of pins thereon engage opposite edges of the web material for holding it as it is treated on the tenter frame. Pinned rolls are provided for engaging and transferring the web material from the pins of the tenter frame, with the web taken off of the tenter chains without loss of control over the web. A cutter unit is for trimming the edges from the web after it has been removed from the tenter chain and while the web remains under control of the pinned rolls, after which trimmed edges are automatically removed from the pins for discarding.
(18) U.S. Pat. No. 5,416,959 to Forrest, Jr.
U.S. Pat. No. 5,416,959 issued to Forrest, Jr. on May 23, 1995 in class 26 and subclass 73 teaches a tenter clip for gripping a web of thermoplastic film between the curved surface of a toggle arm and an anvil surface being tapered at each of its ends. The surface configurations of the toggle arm and anvil define effective surfaces for gripping the film while allowing the film to stretch under these surfaces. Beads are formed at the edges of the web during stretching. These beads wedge into substantially V-shaped gripping regions defined by the toggle arm and the anvil to assist in the stretching operation.
(19) U.S. Pat. No. 5,438,941 to Henz et al.
U.S. Pat. No. 5,438,941 issued to Henz et al. on Aug. 8, 1995 in class 112 and subclass 90 teaches an embroidery machine having horizontally parallel fabric shafts for a vertically arranged embroidery fabric. A plurality of upper and lower horizontal guides are distributed over the length of the machine. One upper and one lower horizontal guide are each connected to a horizontal guide element by vertical connection elements. The horizontal guide elements and the fabric shafts each are vertically adjustable by a positioning drive in guides mounted on the machine.
(20) U.S. Pat. No. 5,555,610 to Young, Jr. et al.
U.S. Pat. No. 5,555,610 issued to Young, Jr. et al. on Sep. 17, 1996 in class 26 and subclass 93 teaches a tenter frame for treating web materials, such as woven or knitted fabrics, film, or the like, to apparatus for removing a web from a tenter while controlling the web, and to a process for removal of a web from a tenter. A pair of endless-opposed tenter chains having a plurality of pins thereon engage opposite edges of the web material for holding it as it is treated on the tenter frame. Pinned rolls are provided for engaging and transferring the web material from the pins of the tenter frame, with the web taken off of the tenter chains without loss of control over the web. A cutter unit is for trimming the edges from the web after it has been removed from the tenter chain and while the web remains under control of the pinned rolls, after which trimmed edges are automatically removed from the pins for discarding.
(21) U.S. Pat. No. 5,797,172 to Hosmer.
U.S. Pat. No. 5,797,172 issued to Hosmer on Aug. 25, 1998 in class 26 and subclass 89 teaches a tenter frame apparatus including an endless chain for carrying tenter clips on one side of a monorail or positioning a web for transport on a single pair of longitudinally aligned bearings carried in horizontal alignment with the web and for guidance on a stationary track by a wear strip first-opposed wear pads opposite the bearings and second-opposed wear pads at the top of the monorail. Since the bearings do not engage drive sprockets at turnarounds, impact and high loads are avoided. In some applications wear strips may be substituted for the bearings.
(22) U.S. Pat. No. 5,862,574 to Poterala.
U.S. Pat. No. 5,862,574 issued to Poterala on Jan. 26, 1999 in class 26 and subclass 89 teaches a tenter frame including low-profile rail assemblies for carrying an endless carrier. A series of attachment blocks of the endless carrier have tentering connectors for transporting a sheet material under widthwise tension in a longitudinal path through the tenter machine. Each rail assembly has guideways for supporting and carrying an endless carrier within the guideways. The tentering system uses a plurality of spherical bearing balls for transporting the endless carrier within slots of the guideways. The endless carrier includes an endless belt or endless chain connecting a series of attachment blocks for holding the bearing balls in a position so that they can freely rotate within the guideways. Tentering connectors are carried by the attachment blocks of the endless carrier for supporting spaced-apart edges of the sheet material. The endless carrier is driven by spaced drive wheels in a closed-loop path to carry the sheet material along the longitudinal path through the tenter machine. A transition guideway section, formed with a plurality of adjacent bending contour plates, provides for angular transitions when connecting together entry, stretch, intermediate, and delivery guideways of rail assemblies. And, a vertically operated closed-loop endless carrier is driven by vertical drive wheels.
(23) U.S. Pat. No. 7,073,237 to Cavanagh.
U.S. Pat. No. 7,073,237 issued to Cavanagh on Jul. 11, 2006 in class 26 and subclass 89 teaches a joint for articulately interconnecting the adjacent ends of rail assemblies in a tenter frame. The rail assemblies are arranged consecutively along a guide path and have parallel guide channels for the advancing and returning legs of continuous chains carrying the clamps gripping the edges of the webs being transversely stretched. The joint includes flexible bands arranged to define intermediate channels connecting the guide channels of the rail assemblies. The flexible bands are resiliently deflected in response to articulation of the rail assemblies to thereby arcuately configure the outer medicate channels.
It is apparent that numerous innovations for tenter frames and related devices have been provided in the prior art that are adapted to be used. Furthermore, even though these innovations may be suitable for the specific individual purposes to which they address, they would not be suitable for the purposes of the embodiments of the present invention as heretofore described, namely, a modular tenter frame rail.